Google is facing a lawsuit over unauthorized in-app purchases on Android devices by children.

The class action suit is brought on behalf of all persons in the U.S. who paid for unauthorized purchases of game currency by their minor children through the Google Play app store. It was filed in the U.S. District Court for the Northern District of California, one of the law firms that filed the suit said Monday.

Many games in the Google Play store are offered free but are designed to induce in-app purchases of virtual supplies, ammunition, fruits and vegetables or cash, the class action law firms involved in the case noted in the complaint.

"These games are highly addictive, designed deliberately so, and tend to compel children playing them to purchase large quantities of game currency, amounting to as much as $100 per purchase or more," according to the complaint.

Google requires users to authenticate their accounts by entering a password prior to purchasing an app or buying in-game currency. But when the password is entered, Google permits the user to make in-app purchases for up to 30 minutes without reentering the password, even if it is a minor, according to the filing.

This enables minors to make expensive in-app purchases without entering a password, "causing Google to pocket millions of dollars" from such transactions with minors, according to the complaint. This is done without the authorization of their parents, whose credit cards or PayPal accounts are automatically charged for the purchases, it added.

The lawsuit, which asks for a jury trial, is seeking damages for affected parents.

The case against Google is similar to one brought by the U.S. Federal Trade Commission against Apple over children's in-app purchases. That case was settled in January and Apple agreed to pay at least US$32.5 million to customers.

Unlike Google, Apple changed its practices so that its users must enter their password to make all in-app purchases, law firm Berger & Montague noted in a news release.

Google did not immediately respond to a request for comment.

Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to loek_essers@idg.com

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